Trefael: the dolmen that became a standing stone

A project to record the prehistoric decoration on the supposedly Bronze Age Trefael stone has revealed the deliberate cannibalisation of an earlier Neolithic monument, and an 8,000 -year focus of human activity. George Nash, Adam Stanford, Carol James, and Thomas Wellicome explain.

The standing stones speckling the valleys and uplands of Western Britain come in all shapes and sizes. Probably once serving as markers to guide communities through the later prehistoric landscape, there are a small number of stones within this varied group that conspicuously fail to conform to the rules of the rest – some are marked with ancient rock art, others display traces of a longer, more complex history. The Trefael stone in south-east Wales is one such monument. Once considered a solitary standing stone, probably erected during the Early Bronze Age, recent research has proved that in a previous life it formed part of a Portal Dolmen, one of Western Europe’s earliest types of Neolithic burial monument.

The Trefael stone is a lump of bluestone measuring about 2.3 by 2m, standing in an isolated field outside the coastal village of Newport, in South-East Wales. It is one of six extant prehistoric monuments occupying the fertile hinterlands of the NevernValley, of which two – Coetan Arthur and Llech y Tribedd – are Portal Dolmens. About 2.7 km to the north lies the double chambered dolmen of Trellyffaint, on whose capstone over 30 faint, eroded cupmarks are visible. Just over 4km west of our site, the Carreg Coatan monument also has a single cupmark on one of its uprights. Multiple examples of these motifs also survive on the surface of the Trefael stone, which first came to archaeological prominence in 1929 when celebrated Welsh archaeologist W.F. Grimes incorporated it into his Pembrokeshire Survey. Prior to 2010, however, no archaeological investigation had been undertaken on the site. Our fieldwork set out to change this.

Initially, our primary interest was recording the monument’s cupmarks. We applied to the Welsh heritage agency Cadw for Scheduled Monument Consent to open a small slot immediately in front of the stone to view its entire surface. Cadw decided that we could gather more information if we put in a larger trench – music to an archaeologist’s ears! It was decided that we would excavate a 4m2 trench immediately east of the stone. Geophysical survey revealed a kidney-shaped anomaly surrounding the stone, measuring c.8m by 6.5m, and resembling the outline of a cairn belonging to a Neolithic Portal Dolmen. No upright stones from this structure had survived – they were likely removed by extensive field clearance and ploughing. During our survey we also observed damage to the northern side of the stone where a large flake had been sheared off, probably by farm machinery.

From standing stone to capstone

Targeted excavation revealed, probably for the first time since the Early Bronze Age, the complete surface of the Trefael stone. Its prehistoric artwork proved more extensive than previously thought. Prior to our research, some 45 cupmarks had been noted on the stone, but by the end of our project we had identified another 30, some arranged in patterns of curving and straight lines. We recorded these using the Valcamonica technique, which involved laying acetate over the stone’s surface and using a colour-coded system to record its boundaries, natural features such as cracks, and features caused by human activity. Each individual peck mark was painstakingly traced, in order to illustrate the rock art decorating the monument.

These were not the only ritualised features uncovered by our research. Over 320 pieces of white quartz were concentrated within an area that extended beyond the cairn. Although white quartz occurs naturally, this unusually high quantity might represent some kind of pavement marking the monument’s façade or entrance. Similar surfaces have been identified outside the famous Knowth passage grave in the Boyne Valley, Ireland, for example. It could be that stone with a particular colour and texture played an important role during the ritual processes associated with the construction, use and display of monuments from this period. Large white quartz boulders were also found in a trench north of the stone, where they partially border the eastern wall of a Bronze Age cist that was centrally-placed within a denuded cairn.

The most exciting developments came as slots within our 4m2 trench reached natural deposits. One of these, in the south-west corner of the trench, exposed what we believe was the original Neolithic land surface, on top of which lay the remains of a tightly compacted cairn. The Trefael stone itself was set in a clear vertical cut sliced into the cairn deposit. This indicated that the ornate standing stone may have been deliberately recycled following its original use as the capstone of a Neolithic Portal Dolmen.

Ritual landscape

When we returned in 2011, the team targeted two trenches based on anomalies picked up during geophysical survey. One revealed human cremated bone and later prehistoric pottery, possibly Grooved Ware, while a probable Early Bronze Age rectangular stone cist – once covered by a circular mound of stone – was identified in the other. As is typical of excavation, however, these finds came in the final hours of the 2011 season and so were reburied – until 2012.

The final part of the 2011 season was to locate a missing standing stone which until relatively recently stood in a neighbouring field to the south. When talking to the current landowners it was revealed that this monolith had been moved some 50 years ago and carefully laid on top of a nearby field boundary. After examining the stone, the team geologists [IsabelleTherriault and Rob Ixer] identified it as an igneous rock, probably Preseli Spotted Dolerite – similar to the standing stones making up the bluestone circle at Stonehenge. While it has yet to be confirmed, we believe that the Trefael Stone may be of a similar local geology.

Last September the team returned once more, to battle the inclement weather, reopen the 2011 trenches, and sink another trench some 35m west of the Trefael Stone. Returning to the trench containing the cremated burial, our most recent excavations revealed further information about the cairn, which survived remarkably intact despite previous ploughing. Directly west of the stone lay a small area of sandy soil that contained the remains of a human cremation burial and associated Late Neolithic pottery. This sub-circular feature, measuring around 0.4m in diameter, was carefully lifted for laboratory analysis and dating. Results are expected in early 2013.

The northern trench containing the disturbed remains of a stone-lined cist and cairn was also further excavated in 2012. The cist proved rectangular in form and was associated with a line of stone and white quartz boulders. Substantial quantities of dark, black earth within the cist are probably the remains of a series of cremated burials. The cist and boulder lines appear to stand directly over a denuded, probably circular, stone cairn. Probably Bronze Age in date, this structure suggests that the landscape in which the Trefael Stone stands was a place of burial for at least 1,500 years.

This is an extract, but the full feature is published in CA 276

Further information: For more information on the project or to enquire about the field school please visit www.rock-art-in-wales.co.uk and the Facebook page http://www.facebook.com/rockartwales.

Source: The authors are founder members of the Welsh Rock art Organisation which is affiliated to the International Federation of Rock art Organisations (IFRAO)

4 thoughts on “Trefael: the dolmen that became a standing stone”

“The Trefael stone is a lump of bluestone measuring about 2.3 by 2m, standing in an isolated field outside the coastal village of Newport, in South-East Wales.”
The Trefael Stome might be in West Wales not South-East?

Apologies, I’m using an iPad for the first time. Not sure how it works. What I was trying to say was the location of the Trefael Stone is in SW Wales, near the village of Newport. Final editorial was out of my hands. George